The Tate Modern in London will next week be filled with 150 tons of seeds as
part of a large art installation.

The floor of its enormous turbine hall will be covered with 15 million replica sunflower seeds made of porcelain, as part of a installation by the Chinese artist Ai Weiwei.

The seeds will form a carpet, eight inches thick. The tiny pieces of porcelain, handmade by labourers in China, were brought to Britain last week.

Visitors will be encouraged to walk and play on the art work, as they did with the remarkable Shibboleth, a giant crack which ran the entire length of the turbine hall, created by Doris Salcedo, the Columbian artist. The seeds will be raked back into position at the end of the day by Tate workers.

The work is the 11th in the popular Unilever series at Tate Modern, which began in 2000 with Louise Bourgeois's giant steel spiders and mirrors.

Other notable artworks that have filled the cavernous turbine hall have included Olafur Eliasson's The Weather Project, with its projection of a giant sun; Carsten Höller's slides which saw visitors shriek with excitement as they hurtled to the ground; and a pitch black room by Miroslaw Balka.

Ai, famous for his work on the Birds Nest Olympic Stadium in Beijing, said that the seeds represented the famines in China under Mao Tse-tung. The porcelain seeds represent what was at times the only food available to millions of Chinese people during Mao's time in power. More than 30 million people starved to death in famines during 1958-61.

"The seeds are the memory of communist times," Ai told The Sunday Times. "We would share them out with friends."

Though Ai was the key designer of the Birds Nest stadium he urged his fellow Chinese not to attend the Olympic Games of 2008, after he said he realised the authorities were using them as a propaganda tool.

He described the Games as "the pretend smile of China", heaping so much embarrassment on Steven Spielberg for his planned involvement in the opening ceremony that the US film director withdrew.